Sound generating apparatus

ABSTRACT

A panel vibration type sound generating display device is disclosed. The display device includes a display panel for displaying an image; a sound generating actuator connected to the display panel and configured to vibrate the display panel to generate sound; a support structure spaced apart from the display panel with an air gap between the support structure and the display panel; and a baffle part disposed between the support structure and the display panel to surround the air gap.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of co-pending U.S. patent applicationSer. No. 17/228,674, filed Apr. 12, 2021, which is a continuation ofU.S. patent application Ser. No. 16/696,847, filed Nov. 26, 2019, nowU.S. Pat. No. 11,019,425, issued May 25, 2021, which is a continuationof U.S. patent application Ser. No. 15/987,267, filed May 23, 2018, nowU.S. Pat. No. 10,555,073, issued Feb. 4, 2020, which is a continuationof U.S. patent application Ser. No. 15/374,566, filed Dec. 9, 2016, nowU.S. Pat. No. 10,009,683, issued Jun. 26, 2018, which claims priorityfrom Korean Patent Application No. 10-2016-0037118, filed on Mar. 28,2016. Each of the above prior U.S. and Korean Patent Applications ishereby incorporated by reference for all purposes as if fully set forthherein.

1. FIELD OF THE INVENTION

The present disclosure relates to a display device and, morespecifically, to a display device for generating sound by directlyvibrating a display panel thereof.

2. DESCRIPTION OF THE PRIOR ART

With the development of various portable electronic devices, such asmobile communication terminals and notebook computers, there has been anincrease in the requirement for a flat panel display device applicablethereto.

The flat panel display devices being researched include a Liquid CrystalDisplay Device, a Plasma Display Panel, a Field Emission Display Device,a Light Emitting Diode Display Device, and an Organic Light EmittingDiode Display Device.

Among these display devices, the Liquid Crystal Display (LCD) deviceincludes: an array substrate including a thin film transistor; an uppersubstrate including a color filter and/or a black matrix; and a liquidcrystal material layer formed therebetween, wherein an alignment stateof the liquid crystal layer is controlled according to an electric fieldapplied between opposite electrodes of a pixel area, and thereby thetransmittance of light is adjusted to display an image.

In a display panel of such a liquid crystal display device, an ActiveArea (AA) configured to provide an image to a user and a Non-active Area(NA), which is a peripheral area of the Active Area (AA), are defined.The display panel is usually manufactured by attaching a firstsubstrate, which is an array substrate having a thin film transistorformed therein to define a pixel area, and a second substrate, which isan upper substrate having a black matrix and/or color filter layerformed thereon, to each other.

The array substrate or first substrate, on which a thin film transistoris formed, includes a plurality of gate lines GS extending in a firstdirection and a plurality of data lines DL extending in a seconddirection perpendicular to the first direction, and one pixel area P isdefined by each gate line and each data line. One or more thin filmtransistors are formed in one pixel area P, and gate and sourceelectrodes of each thin film transistor may be connected to a gate lineand a data line, respectively.

Among these display devices, the liquid crystal display device does nothave its own light-emitting element and thus needs a separate lightsource. Therefore, the liquid crystal display device has a back-lightunit having a light source, such as an LED, which is arranged at therear surface thereof and irradiates a light toward a front surface ofthe liquid crystal panel thereof, thereby at last implementing arecognizable image.

Meanwhile, an Organic Light Emitting Diode (OLED) display device, whichhas recently been in the spotlight as a display device has a fastresponse rate, a high light emitting efficiency, a high luminance and awide viewing angle compared to other conventional devices, because anOLED emits light by itself, i.e., an additional backlight unit is notrequired.

In the organic light emitting diode display device, sub-pixels includingorganic light emitting diodes are arranged in a matrix form, and thebrightness of the sub-pixels selected by a scan signal is controlledaccording to a gray scale of the data. Further, the organic lightemitting diode display device, which is an emissive element, consumes asmaller amount of power and has a high response speed, a high lightemitting efficiency, a high luminance, and a wide viewing angle.

Meanwhile, the above-described display device may be included in a setapparatus or finished produce, such as a television (TV), a computermonitor, or an advertising panel.

Such a display device or set apparatus includes a sound output device,such as a speaker, for generating and outputting sound relating to animage.

Conventionally, a company that manufactures a display device, such as aliquid crystal display device or an organic light emitting diode displaydevice, manufactures only a display panel or display device, whileanother company that manufactures a sound output device assembles thesound output device, such as a speaker, with the manufactured displaydevice, so as to finally complete a set apparatus capable of outputtingboth an image and sound.

FIG. 1 is a schematic plan view of a speaker included in a conventionaldisplay device.

As shown in FIG. 1 , the conventional display device 1 includes aspeaker 2 disposed at a rear or lower part of a display panel thereof.

In this structure, the sound generated by the speaker 2 does notprogress toward a viewer, who is viewing an image from the front side ofthe display device 1, but progresses toward the rear side or theunderside of the display panel. Therefore, the sound may disturb theviewer's immersive experience.

Further, when the sound generated from the speaker 2 progresses towardthe rear side or underside of the display panel, the sound quality maybe degraded due to an interference with sound reflected by a wall orfloor.

Also, the sound generated by a speaker included in conventional displaydevices is not oriented toward a viewer of the display device and maythus undergo diffraction, which decreases sound localization. Moreover,in configuring a set apparatus, such as a TV, a speaker may occupy apredetermined space, which imposes a restriction on the design andspatial arrangement of the set apparatus.

Therefore, there has been an increasing interested in the development oftechnology which can improve the quality of sound output from a displaydevice and prevent the viewer's immersive experience from beingdisturbed.

SUMMARY OF THE INVENTION

The present disclosure has been made to overcome the above-mentionedproblems of the prior art and, in one aspect, provide a panel vibrationtype sound generating display device, which can generate sound bydirectly vibrating a display panel of the display device.

In another aspect, the present disclosure provides a display deviceincluding a panel vibration type sound generating apparatus, which has apredetermined air gap formed between a display panel and a soundgenerating actuator and an actuator support hole formed in a supportstructure of the display device, so that the display device has areduced thickness while having an excellent sound generationperformance. The support structure may also be termed a support memberor support part.

In another aspect, the present disclosure provides a display devicehaving a sound generation baffle part formed therein, which includes anadhesive member attached between the upper surface of the supportstructure and the lower surface of the display panel and a sealing partdisposed outside the adhesive member, so that the display device canminimize sound leakage and improve a sound output characteristic. Theadhesive member may be a double-sided tape.

In another aspect, the present disclosure provides a display device,which includes one or more buffer members arranged between the innersurface of the support structure and the rear surface of the displaypanel adjacent to a source printed circuit board (PCB) or between thesupport structure disposed at the rear surface of the display panel andthe source PCB to fix/support the sound generating actuator, to preventinterference and noise between the support structure and a Source PCB(S-PCB) for driving the display panel.

The panel vibration type sound generating display device may furthercomprise a set PCB, which is disposed at an outer rear surface of thecover bottom and includes a control circuit configured to control theentire display device, wherein a cable passing hole through which aconnection cable for electrically connecting the source PCB and the setPCB is to pass is disposed at an area of the cover bottom correspondingto the first area.

In another aspect, the present disclosure provides a display device inwhich a sound generating actuator is placed at a first position of asupport structure of the display device and a set PCB of a set apparatusis placed at a second position, which is different from the firstposition, so as to avoid interference between the sound generatingactuator and the set PCB, and improve the sound characteristic.

In still another aspect, the present disclosure provides a displaydevice, which has a reinforcement member arranged inside the supportstructure of the display device when two or more sound generatingactuators are used, so that the display device can prevent deformationof the support structure due to different vibration characteristics ofthe two or more sound generating actuators or prevent sound distortionby the vibration of the support structure.

In view of the above aspects, a display device of the present embodimentincludes: a display panel configured to display an image; and a soundgenerating actuator connected to a surface of the display panelconfigured to vibrate the display panel to generate sound. The surfacemay be an inner surface, for example.

The display device may further include a support structure, such as acover bottom, configured to cover and support at least a rear surface ofthe display panel, wherein the sound generating actuator is inserted inand fixed to a support hole formed at the cover bottom to be fixed tothe support structure.

The support structure of the panel vibration type sound generatingdisplay device may comprise: a cover bottom supporting the rear side ofthe display panel, a source PCB for driving the display panel isdisposed on a rear surface of one side of the display panel, and a firstbuffer member spaced from the source PCB by a predetermined distance isplaced on an inner surface of the cover bottom corresponding to thesource PCB.

The sound generating actuator may further include: a plate inserted inthe support hole; a magnet disposed on the plate; a center pole disposedat a center of the plate; a bobbin disposed to surround the center poleand be in contact with the display panel; and a coil wound around thebobbin. The plate may be a lower plate, for example.

The lower plate configuring the sound generating actuator may furtherinclude an extension part extending outward, and the extension part maybe fixed to the lower surface of the cover bottom through a bolt, a PEM™nut, or an adhesive member.

The extension part and the cover bottom of the panel vibration typesound generating display device, may be fixedly coupled to each other byone of a bolt fastened through a through-hole provided through theextension part to a screw hole disposed at the cover bottom and anadhesive member disposed between the extension part and the coverbottom.

The panel vibration type sound generating display device may furthercomprise a baffle part disposed between the support structure and thelower surface of the display panel to define an air gap, which is aspace in which the display panel can be vibrated by the sound generatingactuator.

An air gap is formed between the display panel and the support member,and the display device may further include a baffle part including anadhesive member and a sealing part arranged between the lower surface ofthe display panel and the upper surface of the support member at an edgeof the air gap.

The baffle part of the panel vibration type sound generating displaydevice may comprise an adhesive member disposed at an edge of the airgap and attached to the lower surface of the display panel and the uppersurface of the support structure, and a sealing part disposed outsidethe adhesive member.

The sealing part of the panel vibration type sound generating displaydevice may have a thickness larger than the thickness of the adhesivemember.

The support member includes a cover bottom supporting a rear side of thedisplay panel and a middle cabinet supporting the edge of the displaypanel. The middle cabinet may include an area division member configuredto separate a first area including a source PCB and a second areaincluding a sound generating actuator.

The support structure of the panel vibration type sound generatingdisplay device may comprise a cover bottom, which supports a rear sideof the display panel, and a middle cabinet, which has a shape of aframe, coupled to the cover bottom to support a side surface of thedisplay panel, and stably holds the edge of the display panel, themiddle cabinet comprising an area division member configured to separatea first area including a source PCB for driving the display panel and asecond area including the sound generating actuator.

The baffle part of the panel vibration type sound generating displaydevice may comprise an adhesive member attached to three sides of themiddle cabinet corresponding to the second area, an upper surface of thearea division member, and the lower surface of the display panel, and asealing part disposed outside the adhesive member.

A recessed part is formed on an upper surface of the cover bottomopposite to the source PCB placed on a rear surface of the displaypanel, and a first buffer member spaced a predetermined distance fromthe lower surface of the display panel may be disposed on the recessedpart. The recessed part may be concave, for example.

The cover bottom may have a second buffer member disposed thereon, whichis in contact with the lower surface of the display panel and the uppersurfaces of the cover bottom while separating a first area covering thesource PCB and a second area covering the sound generating actuator.

The sound generating actuator may include two or more actuators, whichare symmetrically arranged and have different vibration characteristics,and the cover bottom may further have a reinforcement member disposedthereon, which passes through adjacent positions of the two or moreactuators.

An embodiment of the present disclosure as described above provides adisplay device including a panel vibration type sound generating displaydevice, which generates sound by directly vibrating a display panel,thereby making it unnecessary to install a separate speaker to thedisplay device or a set apparatus including the display device.

Further, since the progressing direction of the sound coincides with theimage output direction in the display device, the display device or theset apparatus can improve sound localization or sound outputcharacteristics, the mechanism of the set apparatus can be easilydesigned, and can have a reduced thickness thereof.

A concave part of the panel vibration type sound generating displaydevice may be disposed on the inner surface of the cover bottomcorresponding to the source PCB and the first buffer member may bedisposed on an upper surface of the concave part.

The cover bottom of the panel vibration type sound generating displaydevice may have a second buffer member disposed thereon, which is incontact with the lower surface of the display panel and the uppersurfaces of the cover bottom while separating a first area covering thesource PCB and a second area covering the sound generating actuator.

The support structure of the panel vibration type sound generatingdisplay device may comprise a cover bottom supporting the rear side ofthe display panel. The display device may further comprise a set PCB,which is disposed at an outer rear surface of the cover bottom andincludes a control circuit configured to control the entire displaydevice, and a first position in which the sound generating actuator isdisposed and a second position in which one or more boards configuringthe set PCB are arranged do not overlap each other.

The support structure of the panel vibration type sound generatingdisplay device may comprise a cover bottom supporting the rear side ofthe display panel, the sound generating actuator may comprise two ormore actuators, which are symmetrically arranged and have differentvibration characteristics, the cover bottom may have a reinforcementmember disposed thereon, which passes through adjacent positions of thetwo or more actuators.

The two or more actuators of the panel vibration type sound generatingdisplay device may comprise two left sound generating actuators and tworight sound generating actuators, and the reinforcement member may bedisposed to pass through a middle point of a segment connecting the twoleft sound generating actuators and a middle point of a segmentconnecting the two right sound generating actuators.

The panel vibration type sound generating display device may furthercomprise a sound compensation member, which is lengthily disposed at aposition spaced a certain distance apart from an edge of the displaypanel opposite to a moving direction of the sound generating actuatorwhen the sound generating actuator moves to a destination positionspaced a predetermined distance apart from an initial position.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects, features and advantages of the presentinvention will be more apparent from the following detailed descriptiontaken in conjunction with the accompanying drawings, in which:

FIG. 1 is a schematic plan view of a speaker included in a conventionaldisplay device;

FIGS. 2A and 2B are schematic views of a panel vibration type soundgenerating apparatus according to an embodiment of the presentdisclosure wherein FIG. 2A is a plan view and FIG. 2B is a sectionalview;

FIGS. 3A and 3B are sectional views of two types of sound generatingactuators used according to embodiments of the present disclosure;

FIGS. 4A and 4B illustrate a state in which a sound generating actuatoraccording to an embodiment of the present disclosure vibrates a displaypanel to generate sound;

FIGS. 5A and 5B illustrate an example of a coupling state between asound generating actuator according to an embodiment of the presentdisclosure and a cover bottom, which is a supporting structure of adisplay device;

FIGS. 6A and 6B illustrate other embodiments of a coupling state betweena sound generating actuator and a cover bottom;

FIGS. 7A to 7C illustrate an example of a baffle part formed between adisplay panel and a middle cabinet, which is one of the structures forsupporting the display panel to form a sound transferring air gapbetween the display panel, which serves as a vibrating plate, and acover bottom;

FIG. 8 illustrates a structure of a baffle part according to anotherembodiment in which the adhesive member and the sealing part are placeddirectly on a cover bottom;

FIGS. 9A and 9B illustrate a locational relation between a source PCBfor driving a display panel and a set PCB for driving a set apparatus,which are arranged at the rear surface of a display device;

FIGS. 10A and 10B illustrate an embodiment which further includes anarea division member additionally formed on a middle cabinet, and acable passing hole through which a connection cable (FFC) formed on acover bottom passes;

FIGS. 11A and 11B are schematic views showing the relative arrangementof the cover bottom and the source PCB for driving the display panel;

FIGS. 12A and 12B illustrate an embodiment including a buffer membercapable of preventing interference and noise between the source PCB andthe cover bottom illustrated in FIGS. 11A and 11B;

FIG. 13 is a graph illustrating a noise reduction effect when the buffermembers of the embodiment illustrated in FIGS. 12A and 12B are used;

FIG. 14 illustrates a relative arrangement between a sound generatingactuator and a set PCB in a display device according to an embodiment ofthe present disclosure;

FIGS. 15A and 15B illustrate a display device including two or moreactuators symmetrically arranged therein, and a distortion of a coverbottom due to a difference of vibration quantity in the display device;

FIGS. 16A and 16B illustrate a structure which has a reinforcementmember disposed inside a cover bottom in order to prevent generation ofsound distortion by twisting or vibration of the cover bottom;

FIGS. 17A and 17B illustrate specific arrangements of reinforcementmembers on a cover bottom;

FIGS. 18A and 18B illustrate an embodiment, which further includes asound compensation member in order to maintain the sound outputcharacteristics when the sound generating actuator has been verticallymoved; and

FIG. 19 is a graph illustrating a sound output characteristic when apanel vibration type sound generating apparatus according to the presentembodiment is used, in comparison with a conventional speaker.

DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS

Hereinafter, embodiments of the present disclosure will be describedwith reference to the accompanying drawings. In assigning referencenumerals to elements in the drawings, the same elements will bedesignated by the same reference numerals as far as possible althoughthey are illustrated in different drawings. Further, in the followingdescription of the present invention, a detailed description of knownfunctions and configurations incorporated herein will be omitted when itmay make the subject matter of the present invention rather unclear.

In addition, terms, such as first, second, A, B, (a), (b) or the likemay be used herein in describing elements of the present invention. Eachof these terminologies is not used to define an essence, order orsequence of a corresponding component but used merely to distinguish thecorresponding component from other component(s). In the case that it isdescribed that a certain element “is connected to”, “is coupled to”, or“is connected with” another element, it should be understood that notonly can the certain element be directly connected or coupled to theanother element, but an additional element may also be “interposed”between the elements or the elements may be connected or coupled to eachother through an additional element.

FIGS. 2A and 2B are schematic views of a panel vibration type soundgenerating apparatus according to an embodiment of the presentdisclosure, wherein FIG. 2A is a plan view and FIG. 2B is a sectionalview.

As shown in FIGS. 2A and 2B, a display device according to thisembodiment includes a display panel 100 configured to display an image,and a sound generating actuator 200 which is attached to a surface ofthe display panel and vibrates the display panel to generate sound.

The sound generating actuator 200, which is described below in moredetail with reference FIGS. 4A and 4B, includes a magnet, a platesupporting the magnet, a center pole protruding from a central area ofthe plate, and a bobbin disposed to surround the center pole and havinga coil wound thereon, to which an electric current for generating soundis applied, wherein a distal end of the bobbin is attached to onesurface of the display panel.

As shown in FIG. 2B, the display device may include a support structureconfigured to support one or more of the rear surface or a side surfaceof the display panel, and the plate of the sound generating actuator maybe fixed to the support structure.

The support structure includes a cover bottom 300 disposed at the rearsurface of the display panel, and may further include a middle cabinet500 which is coupled to the cover bottom while surrounding the sidesurface of the display panel and receives and supports one side edge ofthe display panel.

The cover bottom configuring the support structure may be a plate-shapedmember made of metal or plastic extending over the entire rear surfaceof the display device.

The cover bottom 300 in the present disclosure is not limited to theterm thereof but may be used as other expressions, such as a platebottom, a back cover, a base frame, a metal frame, a metal chassis, achassis base, or m-chassis, and has a concept including all types offrames or plate-shaped structures, each of which may be arranged on therear base part of the display device as a support for the display panel.

In the present specification, the term “display device” not onlydescribes a display device, such as an OLED module or a Liquid CrystalModule (LCM) including a display panel and a driving unit for drivingthe display panel, but this term also includes a set electronicapparatus or a set apparatus, such as a notebook computer, a television,a computer monitor, or a mobile electronic device such as a smartphoneor an electronic pad, which are finished products including such an LCMor OLED module.

For clarity, an LCM or OLED module configured by a display panel and adriving unit thereof may be expressed as a “display device”, and anelectronic apparatus, as a finished product, including such an LCM orOLED module may be expressed as a “set apparatus”. For example, thedisplay device may include an LCD or OLED display panel and a sourcePCB, which is a control unit for driving the display panel, and the setapparatus may further include a set PCB, which is a set control unitelectrically connected to the source PCB to control the entire setapparatus.

The display panel 100 used in the present embodiment includes all typesof display panels including a liquid crystal display panel, an OrganicLight Emitting Diode (OLED) display panel, and a Plasma Display Panel(PDP) and is not limited to a specific display panel, as long as thedisplay panel is directly vibrated by the sound generating actuator 200to generate sound wave.

When the display panel is a liquid crystal display panel, the displaypanel may include: a plurality of gate lines; a plurality of data lines;pixels defined at intersecting areas between the gate lines and datalines; an array substrate including a thin-film transistor, which is aswitching device configured to adjust a light transmission degree ateach pixel; an upper substrate including a color filter and/or a blackmatrix; and a liquid crystal material layer formed therebetween.

When the display panel is an OLED display panel, the display panel mayinclude: a plurality of gate lines; a plurality of data lines; pixelsdefined at intersecting areas between the gate lines and data lines; anarray substrate including a thin-film transistor, which is a switchingdevice configured to selectively apply a voltage to each pixel; an OLEDlayer disposed on the array substrate; and a sealing substrate or anencapsulation substrate disposed on the array substrate to cover theOLED layer. The sealing substrate protects the thin film transistor andthe OLED layer from external impact and prevents moisture frompermeating the OLED layer.

Although there is no limitation in the type of the display device usedin a display device according to this embodiment, it may be preferredthat the display panel is an OLED display panel by the reasons describedbelow.

Specifically, a liquid crystal display panel has many laminated layersand requires an indirect light source type back-light having a separatelight source disposed therein. Therefore, when the liquid crystaldisplay panel is directly vibrated by the sound generating actuator 200,the directivity of the liquid crystal material may be shaken and thuscause distortion of an image.

In contrast, since the OLED device of the OLED display panel is anemissive element, the OLED display panel does not require a separatelight source and has one panel in which multiple layers including apolarization layer, a glass layer, and an encapsulation layer areintegrated. Therefore, even when the OLED display panel is directlyvibrated by the sound generating actuator 200, the vibration has nearlyno influence on the light emitting property of the organic lightemitting layer and thus causes no image distortion. Therefore, in anembodiment of the present disclosure, an OLED display panel ispreferably used.

The display panel used in a display device according to an embodiment ofthe present disclosure has a general structure, so a more specificdescription thereof will be omitted.

The display device according to an embodiment of the present disclosuremay further include a baffle part 400 configured to form an air gap,which is a space disposed between the display panel and a supportstructure, i.e., the cover bottom 300 or the middle cabinet 500, totransfer the generated sound wave.

That is, by coupling the display panel to the cover bottom at an edge ofthe air gap and sealing the same, the air gap may be defined as an areasealed in all directions, and such a sealed air gap may be expressed asa baffle structure.

Referring to FIGS. 7A to 7C, the baffle part 400 may include an adhesivepart 412 disposed at an edge of the cover bottom or middle cabinet andis attached to the lower surface of the display panel, and a sealingpart 414 disposed outside the adhesive part to reinforce the sealing ofthe air gap 600.

The adhesive part 412 may be configured by a double sided tape. It ispreferred that the height of the sealing part 414 is higher than theheight of the adhesive part 412 as described below in more detail withreference to FIGS. 7A to 7C.

FIGS. 3A and 3B are sectional views of two types of sound generatingactuators used according to embodiments of the present disclosure.

A sound generating actuator 200 used in these embodiments may include amagnet 220, which is a permanent magnet, plates 210 and 210′ configuredto support the magnet, a center pole 230 protruding from a central areaof the plate 210, a bobbin 250 disposed to surround the center pole 230,and a coil 260 wound around the bobbin, wherein an electric current forgenerating sound is applied to the coil 260.

The sound generating actuator used in the present embodiment may includeboth a first structure in which the magnet is disposed outside the coiland a second structure in which the magnet is disposed inside the coil.

FIG. 3A illustrates the first structure having the magnet disposedoutside the coil, which may be called a dynamic type or an externalmagnet type.

In the sound generating actuator of the first structure, the lower plate210 is fixed to a support hole 310 formed at the cover bottom 300 andthe magnet 220, which is a permanent magnet having an annular shape, andis disposed on the lower plate and surrounding the center pole 230.

The upper plate 210′ is disposed on the magnet 220, and an externalframe 240 protruding from the upper plate is disposed outside the upperplate.

The center pole 230 protrudes from the central area of the lower plate210 and the bobbin 250 surrounds the center pole 230.

The coil 260 is wound around a lower portion of the bobbin 250, and theelectric current for generating sound is applied to the coil.

A damper 270 may be disposed between an upper part of the bobbin and theexternal frame 240.

The lower plate 210 and the upper plate 210′ fix the sound generatingactuator 200 to the cover bottom 300 while supporting the magnet 220,the lower plate 210 has a cylindrical shape as shown in FIG. 3A, themagnet 220 having a ring shape is disposed on the lower plate 210, andthe upper plate 210′ is disposed on the magnet.

As the lower plate 210 and the upper plate 210′ are coupled to the coverbottom 300, the magnet 220 disposed between the lower plate 210 and theupper plate 210′ can be fixedly supported.

The plate may be formed of a material having a magnetic property, suchas ferrite Fe. The plate is not limited to the term thereof and may beexpressed by another term, such as a yoke.

The center pole 230 and the lower plate 210 may be integrally formed.

The bobbin 250 is a cylindrical structure formed by paper or aluminumsheet, and the coil 260 is wound around a predetermined lower area ofthe bobbin. A combination of the bobbin and the coil may be referred toas a voice coil.

When the electric current is applied to the coil, a magnetic field isformed around the coil. Then, due to an external magnetic field formedby the magnet 220, the entire bobbin moves upward while being guided bythe center pole according to Fleming's Law.

Meanwhile, since the distal end of the bobbin 250 is attached to therear surface of the display panel 100, the bobbin vibrates the displaypanel based on the application or non-application of the electriccurrent, and such vibrations generate sound waves.

The magnet 220 may be a sintered magnet, such a barium ferrite, or maybe a cast magnet made from an alloy of ferric oxide (Fe2O3), bariumcarbonate (BaCO3), strontium ferrite having an improved magneticcomponent, aluminum (Al), nickel (Ni), and cobalt (Co), without beinglimited thereto.

A damper 270 is disposed between an upper part of the bobbin 250 and theexternal frame 240, and the damper 270 has a wrinkle structure and thuscontracts or expands to adjust the up-down vibration of the bobbinaccording to the up-down movement of the bobbin. That is, since thedamper 270 is connected to the bobbin 250 and to the external frame 240,the up-down vibration of the bobbin is restricted by the restoring forceof the damper 270. Specifically, when the bobbin 250 vibrates upwardbeyond a predetermined height or downward beyond a predetermined level,the restoring force of the damper 270 can return the bobbin to itsoriginal position.

The damper may be expressed by another term, such as an edge.

FIG. 3B illustrates the second structure having the magnet disposedinside the coil, which may be expressed as a micro type or an internalmagnet type.

In the sound generating actuator of the second structure, the lowerplate 210 is fixed to a support hole 310 formed at the cover bottom 300,the magnet 220 is disposed at a central area of the lower plate, and thecenter pole extends upward from the top of the magnet.

The upper plate 210′ protrudes from a peripheral part of the lower plate210, and the external frame 240 is disposed on the edge of the upperplate 210′.

The bobbin 250 is disposed to surround the magnet 220 and the centerpole 230, and the coil 260 is wound around the bobbin.

The damper 270 is disposed between the external frame 240 and thebobbin.

The sound generating actuator of the second structure shown in FIG. 3Bhas a smaller leakage of magnetic flux than that of the first structureshown in FIG. 3A and thus, the corresponding display device can have asmaller size. However, the sound generating actuator of the secondstructure may undergo reduction of magnetic flux due to a large currentinput and is difficult to manufacture.

In these embodiments, both the actuators of the first structure and thesecond structure may be used, and the following description discussesthe first structure as a representative for convenience of description.

The sound generating actuator used in a display device according to anembodiment of the present disclosure is not limited to the typeillustrated in FIGS. 3A and 3B, and includes other types of actuators aslong as the actuators can vibrate a display panel up and down togenerate sound in response to application of the electric current.

FIGS. 4A and 4B illustrate a state in which a sound generating actuatoraccording to an embodiment of the present disclosure vibrates a displaypanel to generate sound.

FIG. 4A illustrates a state in which the electric current has beenapplied, wherein the center pole connected to the lower surface of themagnet serves as the N pole and the upper plate connected to the uppersurfaces of the magnet serves as the S pole to establish an externalmagnetic field between coils.

In this state, if an electric current for generating sound is applied toa coil, an applied magnetic field is generated around the coil. Theapplied magnetic field generates, together with the external magneticfield, a force of moving the bobbin upward.

By the force, the bobbin moves upward and the display panel coupled tothe distal end of the bobbin moves upward, as shown in FIG. 4A.

In this state, if the application of the electric current is interruptedor the electric current is applied in the opposite direction, a force ofmoving the bobbin downward is generated in the same principle, and thedisplay panel thus moves downward.

In this way, according to the direction and magnitude of the electriccurrent applied to the coil, the display panel vibrates up and down togenerate sound wave.

FIGS. 5A and 5B illustrate an example of a coupling state between asound generating actuator according to an embodiment of the presentdisclosure and a cover bottom, which is a supporting structure of adisplay device.

FIGS. 6A and 6B illustrate other embodiments of a coupling state betweena sound generating actuator and a cover bottom.

The sound generating actuator 200 according to an embodiment of thepresent disclosure may be inserted through and supported by a supporthole formed on a cover bottom or back cover, which is a supportstructure of a display device. FIGS. 5A to 6B illustrate various supportstructures.

In the support structure of FIG. 5 , a support hole 310 is formedthrough the cover bottom 300, and at least one among the lower plate 210of the sound generating actuator 200, the magnet 220, and the upperplate 210′ is inserted and received in the support hole.

An extension part 212 extending outward from the lower plate isadditionally formed on the lower surface of the lower plate 210, and theextension part 212 is fixed to the lower surface of the cover bottom 310to allow the sound generating actuator 200 to be mounted to the coverbottom.

In this way, when the sound generating actuator 200 is inserted in andfixed to the support hole formed through the cover bottom, the distancebetween the display panel and the cover bottom can be reduced to therebyreduce the thickness of the display device.

In other words, although an air gap in which the display panel canvibrate should be arranged between the display panel and the coverbottom, the sound generating actuator inserted in/fixed to the supporthole of the cover bottom can minimize the air gap due to the reducedheight of the sound generating actuator disposed between the rearsurface of the display panel and the inner surface of the cover bottom.

In the structure illustrated in FIGS. 5A and 5B, a screw hole is formedon the rear surface of the cover bottom, and a bolt 320 or a screw isfastened through the screw hole formed through the extension part 212 ofthe lower plate to the screw hole of the cover bottom to fix the soundgenerating actuator to the cover bottom.

Meanwhile, in the structure illustrated in FIG. 6A, which is not asimple screw-coupling structure, a PEM™ nut 330 or self-clinching nut isplaced to secure a predetermined distance between the cover bottom 300and the extension part 212 of the lower plate, and the actuator is thenfixed by the bolt 320.

Use of the PEM nut 330 or self-clinching nut as shown in FIG. 6A cansecure a predetermined space between the sound generating actuator andthe cover bottom, thereby minimizing the transfer of the vibrations fromthe actuator to the cover bottom.

In the structure shown in FIG. 6B, an adhesive member, such as adouble-sided tape, is disposed between the cover bottom and theextension part 212 of the lower plate of the actuator to attach and fixthem to each other.

When the adhesive member as shown in FIG. 6B has a properly adjustedelasticity and thickness, the adhesive member can function as a kind ofdamper to minimize the transfer of the vibrations from the actuator tothe cover bottom.

The structures as shown in FIGS. 5A to 6B in which the sound generatingactuator 200 attached to the display panel to directly vibrate thedisplay panel is inserted in and fixed to a support hole formed throughthe cover bottom can reduced the thickness of the display device incomparison with the structure in which the actuator is completelyreceived in the display device.

FIGS. 7A to 7C illustrate an example of a baffle part formed between adisplay panel and a middle cabinet, which is one of structures forsupporting the display panel, in order to form an air gap between thedisplay panel, which serves as a vibrating plate, and a cover bottom.

As shown in FIG. 7A, the panel vibration type sound generating apparatusaccording to this embodiment secures an air gap 600, which is a spaceallowing the panel to be vibrated by the sound generating apparatus 200,between the display panel 100 and a support structure (cover bottom300).

Further, one side of the display panel is coupled to the supportstructure of the display panel to generate sound waves during thevibration of the display panel. Especially, the generated sound shouldnot leak to the outside through a side, etc. of the display device.

To this end, the display device according to this embodiment has abaffle part 400 formed between the lower surface of the display paneland the support structure.

Specifically, it is preferred that a predetermined section (that is, airgap) is defined around the sound generating actuator, a baffle part isdisposed between the upper surface of the cover bottom or middle cabinetand the lower surface of the display panel at an edge of the section,and the baffle part 400 includes an adhesive member 412, such as adouble-sided tape, attached between the lower surface of the displaypanel and the upper surface of the support structure of the displaydevice, and a sealing part 414 disposed outside the adhesive member.

The section in which the baffle part is formed may be the entire displaypanel area defined by four outer sides of the display panel. However,the section is not limited to such a definition and may be defined by anarea excluding the area in which a source PCB is disposed, as describedbelow.

When two or more sound generating actuators are arranged to implementstereo or three-dimensional sound, two or more sections may beseparately arranged to form the baffle part.

As shown in FIGS. 7A to 7C, the support structure of the display devicemay include a middle cabinet 500, which is coupled to the cover bottomand is configured to allow a part of the display panel to be stablyplaced thereon, in addition to the cover bottom 300 covering the entirerear surface of the display panel.

The middle cabinet 500 is a frame-shaped member formed along the outerperiphery of the display panel, and includes a horizontal support part502 on which a part of the display panel is stably placed, and avertical support part 504 bent perpendicularly in opposite directionsfrom the horizontal support part to cover the side surface of the coverbottom and the side surface of the display panel. Therefore, the middlecabinet may have a shape of a letter “T” in general.

The middle cabinet 500 configures an external ornamental part of theside surface of the display device or set apparatus, and may not be usedor integrally formed with the cover bottom in some cases.

According to the embodiment of FIG. 7A, the adhesive member 412configuring the baffle part 400 is a double-sided tape disposed betweenthe upper surface of the horizontal support part of the middle cabinet500 and the display panel and fixes the lower surfaces of the displaypanel to the middle cabinet.

The sealing part 414 configuring the baffle part is placed outside ofthe adhesive member and preferably has a thickness or height larger thanthe thickness or height of the adhesive member.

The sealing part 414 may be made from a material having a largeelasticity, such as rubber, and has a thickness t2 larger than thethickness t1 of the adhesive member 412 as illustrated in FIG. 7B.

That is, as illustrated in FIG. 7B, one adhesive surface of the adhesivemember 412, which is a double-sided tape having a thickness t1, isattached to the inner part of the upper surface of the horizontalsupport part 502 of the middle cabinet 500, and the sealing part 414made of an elastic material having a thickness larger than t1 isdisposed outside the adhesive member.

In this state, the display panel 100 is attached to the other adhesivesurface of the adhesive member 412. Then, the display panel is attachedto the middle cabinet while pressing, to a certain degree, the sealingpart 414 having the larger thickness. (FIG. 7C)

As a result, the sealing of the air gap around the sound generatingactuator is further enhanced.

The structure illustrated in FIG. 7C, in which the display panel 100 andthe cover bottom 300 are coupled to each other while forming the air gap600 to be as wide as the thickness of the adhesive member 412 and thehorizontal support part 502 of the middle cabinet, can secure avibration space in which the display panel can generate sound, and canprevent the internally generated sound waves from leaking to the outsidealong the side surface of the display device.

The baffle part 400 disposed at an edge of the air gap, which has adouble structure of the adhesive member 412 and the sealing part 414while allowing the sealing part to have a larger thickness, can furtherenhance the sealing of the air gap and prevent leakage of the sound.

It should be construed that the middle cabinet 500 used in the presentspecification may be replaced by another term, such as a guide panel, aplastic chassis, a p-chassis, a support main, a main support, or a moldframe, and includes all types of members, which are structures having ashape of a four-sided frame and having a sectional shape includingmultiple bent portions and are connected to the cover bottom to be usedto support the display panel and the baffle part.

The middle cabinet 500 may be made of synthetic resin, such as apolycarbonate, by injection molding, without being limited thereto.

FIG. 8 illustrates a structure of a baffle part according to anotherembodiment in which the adhesive member and the sealing part are placeddirectly on a cover bottom.

Although a middle cabinet is used to support the cover bottom and thedisplay panel in the embodiment described above, the middle cabinet maynot be always required.

The embodiment illustrated in FIG. 8 shows a structure in which thecover bottom 300 supports one side of the display panel while forming anexternal appearance of the side surface of the display device without amiddle cabinet.

The structure illustrated in FIG. 8 includes a cover bottom 300 in whicha step portion 360 protrudes upward from a base surface at one side ofthe cover bottom 300 and a side surface supporting part 362 verticallyextends from the outside of the step portion 360.

A part of the edge of the display panel 100 is stably placed on andattached to the step portion 360 of the cover bottom 300, the sidesurface support part 362 of the cover bottom surrounds and protects theside surface of the display panel 100, and the cover bottom resultantlyforms an external ornamental part of the entire side and rear surfacesof the display device.

In this structure, in order to configure the baffle part 400 forgeneration of sound, the adhesive member 412 in the form of adouble-sided tape is disposed inside the step portion 360 of the coverbottom and the sealing part 414 having a thickness larger than that ofthe adhesive member is disposed outside the adhesive member.

In this state, the display panel 100 is placed on the step portion 360of the cover bottom and is attached to one adhesive surface of theadhesive member 412, so that the display panel is coupled to the coverbottom. Then, the sealing part 414 is compressed to secure and enhancethe sealing of the air gap for transfer of sound.

The embodiment of FIG. 8 has a simple structure without a middle supportstructure like the middle cabinet and includes the baffle part 400,which is disposed at an edge of the air gap and has a double structureof the adhesive member 412 and the sealing part 414 while allowing thesealing part to have a larger thickness. Therefore, the embodiment ofFIG. 8 can secure a vibration space in which the display panel cangenerate sound, and can prevent the internally generated sound wavesfrom leaking to the outside along the side surface of the displaydevice.

The thickness of the air gap, that is, the distance G between thedisplay panel and the cover bottom, may have a value of about 1.0 to 3.0mm in an embodiment of the present disclosure. However, the thickness isnot limited to the range and may have a value in a range differentaccording to the degree of vibration of the display panel, etc.

However, in order to reduce the thickness of the display device, it ispreferable to minimize the thickness G of the air gap in considerationof the quantity of vibration of the display panel by the soundgenerating actuator, the range of sound to be output, and the quantityof output. In an embodiment of the present disclosure, an optimumthickness of the air gap G is about 2.0 mm.

FIGS. 9A and 9B illustrate a locational relation between a source PCBfor driving a display panel and a set PCB for driving a set apparatus,which are arranged at the rear surface of a display device.

As shown in FIGS. 9A and 9B, the display device includes a source PCB,which is a circuit board including a Source Driver Integrated Circuit(S-DIC) for driving a display panel to drive data lines formed on thedisplay panel and is referred to as simply “S-PCB”.

The display device or a set apparatus including the same is connected tothe S-PCB and may further include a Control Printed Circuit Board(C-PCB) having control parts and various electric devices mountedthereon to generally control the display device or set apparatus.

Specifically, an OLED display device, to which the present embodiment isapplicable, may include: an OLED display panel 100 including a pluralityof data lines DL, a plurality of gate lines, and a plurality ofsub-pixel SP arranged thereon; a data driver configured to drive theplurality of data lines DL; a gate driver configured to drive theplurality of gate lines GL; and a controller configured to control thedata driver and the gate driver.

The controller supplies various control signals to the data driver andthe gate driver to control the data driver and the gate driver, startsscanning according to a timing implemented in each frame, converts imagedata input from the outside into a data signal format used in the datadriver and outputs a converted image data, and properly controls thedriving of the data driver according the scanning.

The controller may be a timing controller used in a general displaytechnology or may be a control apparatus including a timing controllerto further perform another control function.

The data driver supplies a data voltage to the plurality of data linesDL to drive the data lines DL. Herein, the data driver is also referredto as a “source driver”.

The data driver may include at least one Source Driver IntegratedCircuit (S-DIC) to drive the plurality of data lines.

The gate driver sequentially supplies a scan signal to the plurality ofgate lines GL to sequentially drive the gate lines GL. The gate driveris also referred to as a “scan driver” and may include at least one GateDriver Integrated Circuit (G-DIC).

Each Source Driver Integrated Circuit (S-DIC) may be connected to abonding pad of an OLED display panel either by a Tape Automated Bonding(TAB) method or a Chip On Glass (COG) method or directly. In some cases,S-DICs may be integrated and arranged in an OLED panel. Further, eachS-DIC may be packaged on a film connected to an OLED display panel by aChip On Film (COF) method.

That is, a display device, to which the present embodiment isapplicable, may include: at least one Source Printed Circuit Board(S-PCB) necessary for circuit connection of at least one Source DriverIntegrated Circuit (S-DIC); and a Control Printed Circuit Board (C-PCB)or set PCB configured to mount control parts for controlling the entiredisplay device and various electric devices thereon.

Here, at least one S-DIC may be mounted on or a Chip-On Film (COF)having at least one S-DIC mounted thereof may be connected to the atleast one source PCB.

The C-PCB or set PCB 800 may include a controller configured to controloperations of the data driver and the gate driver, and a PowerManagement IC (PMIC) configured to supply various voltages or currentsto the display panel, the data driver, and the gate driver or controlthe various voltages or currents to be supplied.

The source PCB is usually located at one side among the upper side andthe lower side of a display panel. However, according to the drivingscheme or panel design scheme, the source PCB may be arranged on boththe upper side and the lower side.

That is, as shown in FIGS. 9A and 9B, the source PCB 700 is connected tothe display panel 100 and the COF 710 and is disposed on a lower rearsurface of the display panel.

The C-PCB or set PCB 800 may be disposed at the outer rear side of thecover bottom 300 and connected through a flexible cable to the sourcePCB 700 located inside the cover bottom.

In the structure shown in FIGS. 9A and 9B, it is difficult to configurea baffle part as described above with reference to FIGS. 7A to 7C, atthe lower side of the display panel having the sound generating actuator200 mounted thereon.

In other words, since the source PCB 700 and the chip-on film 710connected thereto are arranged in the vicinity of the lower side of thedisplay panel, it is difficult to arrange the baffle part 400 includingthe adhesive member 412 and the sealing part 414, and the sealing of theair gap may be degraded even when the baffle part is arranged.

Further, the generated sound may leak backward through a cable passinghole, which is formed through a part at the lower side of the coverbottom to enable a flexible cable for connection between the source PCB700 disposed inside the cover bottom and the set PCB 800 disposedoutside the cover bottom to pass therethrough.

Therefore, in order to apply a sound generating apparatus of the presentembodiment to a display device having the structure as shown in FIGS. 9Aand 9B, it is necessary to solve the problems of degradation in thesealing of the baffle part and the sound leakage. In this respect, anembodiment, as shown in FIGS. 10A and 10B, is presented.

The embodiment illustrated in FIGS. 10A and 10B has a structure, whichfurther includes an area division member 510 configured to partition themiddle cabinet into two or more areas and has a baffle part formed onthe area division member, in order to solve the problems of thestructure described above with reference to FIGS. 9A and 9B. Thisembodiment also includes a cable passing hole through which a connectioncable (FFC) formed on a cover bottom passes.

The area division member 510 divides the entire area of the middlecabinet surrounding the entire display panel into a first area A inwhich the source PCB is included and a second area B in which the sourcePCB is not included, wherein the sound generating actuator 200 isdisposed in a part of the second area B.

The area division member may be manufactured in the form of a bar havinga thickness corresponding to the horizontal support part of the middlecabinet to be attached to the middle cabinet 500 through welding, etc.However, the present disclosure is not limited thereto and the entiremiddle cabinet including the area division member 510 may be integrallymanufactured as one unit.

As shown in FIG. 10A, an area division member 510 is lengthily disposedin the horizontal direction of the display device, and an adhesivemember 412 and a sealing part 414 are arranged on the upper side of thearea division member 510 and three sides of the middle cabinetcorresponding to the second area B.

FIG. 10B is a sectional view taken along line I-I′ of FIG. 10A, in whichthe adhesive member 412 and the sealing part 414 are arranged on theupper side of the area division member 510 to seal the second area B asan air gap.

In a part of the lower area of the cover bottom 300, specifically, amongthe areas divided by the area division member 510, a cable passing hole370, through which a connection cable 810 connecting the source PCB 700and the set PCB 800 is to pass, is formed in the first area A, whichincludes the source PCB.

The structure as shown in FIGS. 10A and 10B in which only the secondarea B, which does not include a source PCB is formed as a soundgenerating area can minimize the degradation of the sealing of the soundgenerating area by interference of the source PCB.

Further, the cable passing hole 370 disposed in the first area Aincluding the source PCB can prevent sound leakage through the cablepassing hole.

FIGS. 11A and 11B are schematic views showing the relative arrangementof the cover bottom and the source PCB for driving the display panel.

As shown in FIG. 11A, a source PCB 700 including an S-DIC or data driveris connected to the display panel through a chip-on film, etc., and isdisposed at one side (lower side) of the display panel.

As shown in FIG. 11B, a gap g is formed between the source PCB and thecover bottom in the area in which the source PCB is disposed, and issmaller than a gap between the source PCB and the cover bottom in theother area.

Therefore, when the sound generating actuator 200 according to thepresent embodiment is arranged and vibrates the display panel, thesource PCB, which integrally vibrates the display panel, may collidewith the cover bottom in the area in which the source PCB is placed.

The collision between the source PCB and the cover bottom may generatenoise and may even damage the source PCB.

Further, even without direct collision between the source PCB and thecover bottom, strong vibrations of the display panel at the time ofsound generation may have an influence on the performance of the sourcePCB when the vibration is continuously transferred to the source PCB.

In order to solve this problem, arranging a buffer member for protectingthe source PCB between the source PCB and the cover bottom or betweenthe display panel and the cover bottom is proposed.

FIGS. 12A and 12B illustrate an embodiment including a buffer membercapable of preventing interference and noise between the source PCB andthe cover bottom illustrated in FIGS. 11A and 11B.

In the embodiment of FIGS. 12A and 12B, a source PCB 700 including acircuit element for driving the display panel is disposed at the rearsurface of the display panel, a recessed part 380 is formed in an areaof the cover bottom, which faces the source PCB, and a first buffermember 910 having a predetermined elasticity is placed on the uppersurface of the concave part 380. The recessed part 380 may be concave,for example.

Further, a second buffer member 920 extending along a length of onedirection may be additionally disposed on the cover bottom.

Specifically, as shown in FIG. 12A, the display panel may be dividedinto a first area A covering the source PCB and a second area B coveringthe sound generating actuator, and the second buffer member 920 ispreferably disposed as being extended along a length of the first area Aand second area B to separate the first area A and the second area Bfrom each other.

Of course, although not illustrated, the baffle part 400 including theadhesive member 412 and the sealing part 414 described above withreference to FIGS. 7A to 8 may be disposed on all of the four sides ofthe display panel in the embodiment of FIGS. 12A and 12B.

The first buffer member 910 and the second buffer member 920 may beconfigured by a one-sided tape or double-sided tape. However, thepresent disclosure is not limited thereto, and the buffer member mayinclude all types of members formed of rubber, plastic, paper, or othermaterials, which have a predetermined elasticity.

It is preferred that the first buffer member 910 is disposed on theconcave part 380 of the cover bottom while the upper surface of thefirst buffer member 910 is spaced a predetermined distance apart fromthe source PCB and the second buffer member 920 has one surface incontact with the cover bottom and the other surface in contact with thelower surface of the display panel.

Of course, the first buffer member 910 may be placed on a part of theupper surface of the cover bottom, which faces the source PCB.

As shown in FIG. 12B, the concave part 380 formed at the cover bottomarea corresponding to the source PCB increases the gap between thesource PCB and the cover bottom to reduce the possibility that thesource PCB may collide with the cover bottom even when the display panelvibrates to generate sound.

Moreover, the first buffer member 910 disposed on the concave part 380of the cover bottom can buffer a large vibration of the display paneleven when the source PCB moves toward the concave part of the coverbottom due to the larger vibrations, so as to reduce the generation ofnoise due to interference between the source PCB and the cover bottomand reduce the possibility of damage to the source PCB.

Further, when the display panel vibrates in the second area B, which isthe sound generation area, the second buffer member 920 can prevent thevibration from being transferred to the source PCB 700 disposed on therear surface of the display panel to some degree, and thus can minimizethe degradation of performance of the source PCB due to continuousvibration of the display panel.

The location of the sound generating actuator may be changed accordingto the arrangement of the second buffer member 920.

That is, as shown in FIG. 12A, when the second buffer member 920 isspaced a distance d apart from the lower side of the display panel, thesound generating actuator 200 may be moved by about 2d from the initialposition P1 and is then installed at position P2.

Changes in the sound output characteristics according to theinstallation of the second buffer member can be minimized by moving thesound generating actuator by about twice that of the space d between thesecond buffer member 920 and one side of the display panel.

FIG. 13 is a graph illustrating a noise reduction effect in the case ofusing the buffer members of the embodiment illustrated in FIGS. 12A and12B.

As a result of actual experiments, it has been confirmed that, when thefirst buffer member 910 and the second buffer member 920 described abovewith reference to FIGS. 12A and 12B are not used, unnecessary excessivenoise was generated in a low sound range of several dozens of Hz and ina sound range of 1000 Hz or higher, as noted from the dotted line ofFIG. 13 .

In contrast, as noted from the solid line of FIG. 13 , the noise islargely reduced in the corresponding bands when the buffer members ofFIGS. 12A and 12B are used.

FIG. 14 illustrates a relative arrangement between a sound generatingactuator and a set PCB in a display device according to an embodiment ofthe present disclosure.

In general, a display device or a set apparatus including the displaydevice includes not only a source PCB including a control circuit (datadriver IC, etc.) for driving a touch function or a data line of adisplay panel, but also a set PCB connected to the source PCB to controlthe display device or the entire set apparatus and supply power thereto.

As described above with reference to FIGS. 10A and 10B, the source PCBis attached to the rear surface of the display panel and the set PCB isattached to the outer side of the rear surface support structure of thedisplay device, such as a cover bottom or a back cover.

The embodiment of FIG. 14 provides a display device in which a soundgenerating actuator is placed at a first position of a support structureof the display device and a set PCB of a set apparatus is placed at asecond position different from the first positions, so as to avoidinterference between the sound generating actuator and the set PCB.

As illustrated in FIG. 14 , the set PCB 800 placed on the rear surfaceof the cover bottom may include a power board 810 configured to supplypower to the display panel, a timing controller 820 configured togenerate a timing pulse or a timing signal for driving a gate line ordata line, and a main board 830 including a control circuit forcontrolling the entire display device or set apparatus.

Boards 810, 820, and 830 of the set PCB 800 are attached to the rearsurface of the cover bottom 300, and the sound generating actuator 200is fixedly inserted in a support hole formed through the cover bottom asdescribed above.

Therefore, it is preferable to place the sound generating actuator 200(first position) and the set PCB (second position) at differentpositions, as shown in FIG. 14 , to avoid interference therebetween.

Even when the sound generating actuator 200 is fixed within the coverbottom, if the positions of the sound generating actuator and the setPCB overlap, the vibration of the sound generating actuator may becontinuously transferred to the circuit elements of the set PCB to havea bad influence on the performance of the set PCB.

Therefore, the arrangement of the sound generating actuator 200 (firstposition) and the set PCB (second position) at different positions asshown in FIG. 14 facilitates the arrangement design of elements and canminimize the degradation of the performance of the set PCB.

FIGS. 15A and 15B illustrate a display device including two or moreactuators symmetrically arranged therein, and a distortion of a coverbottom due to a difference of vibration quantity in the display device.

According to the embodiment shown in FIGS. 15A and 15B, a plurality ofsound generating actuators may be symmetrically arranged at left andright portions or upper and lower portions of the display panel tooutput different sounds at the areas.

For example, as shown in FIG. 15A, in order to implement stereo sound,one or two left sound generating actuators 1210 and 1210′ are arrangedat the left side of the display panel, one or two right sound generatingactuators 1220 and 1220′ are arranged at the right side of the displaypanel, and the left and right actuators may be differently vibrated.

As shown in FIG. 15B, which is a sectional view taken along line II-II′of FIG. 15A, when the different vibrations of the left and rightactuators 1210 and 1220 are continuously repeated, the vibrationdifference between the left side and right side of the cover bottom 1300is continuously accumulated.

Since the cover bottom is usually manufactured to have as thin athickness as possible, the accumulation of the vibration differencebetween the left side and right side of the cover bottom may cause thecover bottom to be curved or deformed. That is, as shown in FIG. 15B,the cover bottom 1300 may be twisted or deformed. Further, even when thecover bottom 1300 is not deformed, the vibration difference of the coverbottom due to the vibration difference between the left and rightactuators may cause distortion of the generated sound.

In order to solve this problem, a structure as shown in FIGS. 16A and16B, which has a reinforcement member disposed inside a supportstructure of a display device while using two or more sound generatingactuators is proposed.

This structure prevents the generation of sound distortion by twistingor vibration of the cover bottom.

In the embodiment illustrated in FIGS. 16A and 16B, at least onereinforcement member 1310 may be disposed inside or outside of the coverbottom in order to prevent deformation of the cover bottom or sounddistortion by the unbalanced vibration of the cover bottom in the caseof using multiple sound generating actuators having different vibrationcharacteristics as described with reference to FIGS. 15A and 15B.

The reinforcement member 1310 may be formed to have a shape of a longbar passing through a portion adjacent to multiple sound generatingactuators and are preferably arranged at particular positions tooptimize the reinforcement characteristics.

As shown in FIG. 16A, when two left sound generating actuators 1210 and1210′ and two right sound generating actuators 1220 and 1220′ arearranged, the reinforcement member 1310 may be disposed to extendthrough a middle point Q between the two left sound generating actuators1210 and 1210′ and a middle point Q′ between the two right soundgenerating actuators 1220 and 1220′.

This arrangement can optimize the reinforcement performance of thereinforcement member 1310 even when the two left and right soundgenerating actuators have different vibration characteristics.

The reinforcement member 1310 may be manufactured in the form of aseparate metal bar and is then attached to the inner surface of thecover bottom as shown in FIG. 16B, to which the present disclosure isnot limited.

For example, the cover bottom may be manufactured through injectionmolding, and may have a reinforcement member 1310 integrally formed byprotruding a part of the inner surface of the cover bottom.

The reinforcement member 1310 is not inevitably disposed on the innersurface of the cover bottom, but may be disposed on the outer surface ofthe cover bottom. However, in consideration of an external appearanceand the thickness of the display device, it is preferred that thereinforcement member is disposed on the inner surface of the coverbottom 1300.

FIGS. 17A and 17B illustrate specific arrangements of reinforcementmembers on a cover bottom.

FIG. 17A illustrates a structure in which three sound generatingactuators are arranged at each of the left side and right side thereofand two reinforcement members 1310 and 1310′ are arranged, wherein afirst reinforcement member 1310 is disposed to extend through middlepoints Q-Q′ of segments, each of which connects to two upper actuatorsamong the three left or right sound generating actuators, and a secondreinforcement member 1310′ is disposed to extend through middle pointsS-S′ of segments, each of which connects to two lower actuators amongthe three left or right sound generating actuators.

FIG. 17B illustrates a structure in which only one left actuator andonly one right actuator are arranged and the reinforcement member 1310is disposed to extend through centers of the left and right actuators1210 and 1210′. In this structure, two divided reinforcement members maybe formed in consideration of the arrangement structure of the actuatorsinserted in and supported by the cover bottom.

The symmetric arrangement of two or more sound generating actuatorshaving different vibration characteristics as described above canprevent deformation (twisting) of the cover bottom due to the differentvibration characteristics of the sound generating actuators or sounddistortion by the vibration of the cover bottom.

FIGS. 18A and 18B illustrate an embodiment, which further includes asound compensation member in order to maintain the sound outputcharacteristics when the sound generating actuator has been verticallymoved by a reason of design.

FIG. 18A illustrates a state in which a sound generating actuator 200 isdisposed at an initial position P3 having an optimal sound outputcharacteristic.

However, the sound generating actuator may have to be moved by apredetermined distance D from the initial position P3 in order tomaintain a lower thickness of the upper end portion or by reasonsrelating to design or arrangement of parts.

In this case, only a simple movement of the sound generating actuatorchanges the relative position with respect to the baffle part 400 andmay thus degrade the sound output characteristics.

Therefore, in such a case, if the sound generating actuator is moved toa destination position P4 spaced a movement distance D apart from theinitial position P3, a lengthy sound compensation member 1400 ispreferably placed at a position spaced 2D apart from an edge (side)opposite to the moving direction.

That is, as shown in FIG. 18B, when the sound generating actuator ismoved downward to a position P4 spaced apart by D from the initialposition P3 by a reason relating to design, a sound compensation member1400 extending along the length of the horizontal direction is placed ata position spaced apart by 2D from the upper edge of the display panel.The arrangement of a sound compensation member at a positioncorresponding to twice that of the moving distance D of the soundgenerating actuator enables the moved actuator to be located in themiddle of the changed air gap by the sound compensation member, therebyminimizing the change in the sound generation characteristics accordingto the movement of the actuator.

The sound compensation member 1400 may be implemented by a double-sidedtape disposed between the cover bottom and the display panel.

As described above, when it is necessary to change the position of asound generating actuator, a sound compensation member may be placed ata position proportional to the moving distance, to maintain the relativeposition of the actuator in the entire air gap, thereby preventing thesound characteristics from changing according to the movement of theactuator.

FIG. 19 is a graph illustrating a sound output characteristic in thecase of using a panel vibration type sound generating apparatusaccording to an embodiment of the present disclosure, in comparison witha conventional speaker.

As a result of an actual experiment, a rapid sound intensity reduction(sound pressure reduction) as illustrated by a dotted line in FIG. 19was observed in the middle/high sound range of 4000 Hz or higher when aspeaker disposed at the rear surface or the lower end as shown in FIG. 1separately from the display panel.

In contrast, as illustrated by a solid line in FIG. 19 , the structureaccording to this embodiment, in which a sound generating actuator isfixed to a support structure to directly vibrate the display panel, canreduce the sound pressure in the middle/high sound range, and especiallycan greatly improve the sound output characteristic in the high soundrange.

As a result, use of the present embodiment can provide rich sound outputin all sound ranges.

According to the present embodiment as described above, one or moresound generating actuators are fixed to a support structure to directlyvibrate the display panel. Therefore, the progressing direction of thesound coincides with the image output direction to enhance the soundlocalization and improve the sound output characteristics in a widesound range.

Further, since a display device or a set apparatus does not require aseparate speaker, the mechanism of the set apparatus can be easilydesigned and the thickness of the display device or set apparatus can bereduced.

Especially, a predetermined air gap is formed between the display paneland the sound generating actuator and the sound generating actuator isinserted in and fixed to a support hole formed at a support structure ofthe display device. Therefore, the display device has an excellent soundgeneration performance while having a reduced thickness.

Further, a baffle part, which includes an adhesive member (double-sidedtape) attached between the upper surface of the support structure andthe lower surface of the display panel and a sealing part disposedoutside the adhesive member, can minimize sound leakage and improve thesound generating performance.

Further, the arrangement of one or more buffer members between a sourcePCB of the display panel and the support structure disposed at the rearsurface of the display panel to fix/support the sound generatingactuator or between the inner surface of the support structure and therear surface of the display panel adjacent to the source PCB can preventgeneration of interference and noise between the support structure ofthe display device and a source PCB (S-PCB) for driving the displaypanel.

Also, the arrangement of a reinforcement member on the support structureof the display device when two or more sound generating actuators areused can prevent deformation of the support structure due to differentvibrations of the two or more sound generating actuators.

The above description and the accompanying drawings provide an exampleof the technical idea of the present invention for illustrative purposesonly. Those having ordinary knowledge in the technical field, to whichthe present invention pertains, will appreciate that variousmodifications and changes in form, such as combination, separation,substitution, and change of a configuration, are possible withoutdeparting from the essential features of the present invention.Therefore, the embodiments disclosed in the present invention areintended to illustrate the scope of the technical idea of the presentinvention, and the scope of the present invention is not limited by theembodiment. The scope of the present invention shall be construed on thebasis of the accompanying claims in such a manner that all of thetechnical ideas included within the scope equivalent to the claimsbelong to the present invention.

What is claimed is:
 1. An apparatus, comprising: a vibrating plate; atleast two sound generating actuators respectively disposed at differentareas of the vibrating plate and respectively configured to vibrate thedifferent areas of the vibrating plate to generate sound; a supportstructure on a rear surface of the vibrating plate; a printed circuit ata rear of the vibrating plate; and an area division member at a rearportion of the vibrating plate, the area division member dividing anarea at the rear portion of the vibrating plate into a first areaincluding the printed circuit and a second area including the at leasttwo sound generating actuators.
 2. The apparatus of claim 1, furthercomprising a baffle part disposed between the support structure and thevibrating plate to form an air gap between the support structure and thevibrating plate.
 3. The apparatus of claim 2, wherein the baffle part isdisposed at a periphery of the second area between the support structureand the vibrating plate to surround the air gap in the second area. 4.The apparatus of claim 2, wherein the vibrating plate is configured togenerate sound waves in the air gap when vibrated by the at least twosound generating actuators, and wherein the baffle part surrounds theair gap to reduce leakage of the sound waves out of the air gap.
 5. Theapparatus of claim 2, wherein the baffle part comprises at least one ofan adhesive member and a sealing part disposed outside of the adhesivemember.
 6. The apparatus of claim 1, further comprising a reinforcementmember extending between a sound generating actuator and another soundgenerating actuator among the at least two sound generating actuators.7. The apparatus of claim 6, wherein the reinforcement member isdisposed apart from the sound generating actuator and the other soundgenerating actuator.
 8. The apparatus of claim 1, wherein the supportstructure comprises: a cover bottom covering the rear portion of thevibrating plate; and a middle cabinet supporting a periphery of thevibrating plate.
 9. The apparatus of claim 1, wherein the supportstructure comprises: a recessed part disposed in an inner surface of thesupport structure, the recessed part being disposed opposite the printedcircuit; and a first buffer member in the recessed part between thesupport structure and the printed circuit.
 10. The apparatus of claim 1,wherein each of the at least two sound generating actuators isconfigured to vibrate the vibrating plate to generate sound projectingin a direction coinciding with an image output direction of thevibrating plate to localize the output sound.
 11. The apparatus of claim1, further comprising a baffle part at a rear portion of the vibratingplate separating one of the different areas from another of thedifferent areas.
 12. The apparatus of claim 1, wherein the at least twosound generating actuators are configured to generate a stereo sound.13. The apparatus of claim 1, wherein the at least two sound generatingactuators are symmetrically arranged.
 14. The apparatus of claim 1,wherein the at least two sound generating actuators are configured togenerate different vibrations from one another to generate differentsounds in the different areas of the vibrating plate.
 15. The apparatusof claim 1, wherein the thickness of the air gap is from about 1.0 mm to3.0 mm.
 16. The apparatus of claim 1, further comprising a soundcompensation member.